224 



NAIURJi 



[January 9, 1902 



SCIENTIFIC BALLOONING. 



'X'HE exploration of the upper air has become increas- 

 ■^ ingly attractive as a branch of meteorological 

 inquiry, and the soundings of the ocean of air, to 

 use Mr. Rotch's expression, may ht held to include ob- 

 servations at high-level stations, records olnained from 

 instruments carried by kites or unmanned balloons, as 

 well as observations made by travellers in free balloons. 

 Of these the last mentioned offer most attractions for 

 the adventurous, and they form an essential part of 

 scientific inquiry, because eye observations can be taken 

 of clouds and other atmospheric phenomena from a point 

 of view not otherwise attainable, and experiments that 

 throw light upon the working of various instruments can 

 be carried out under conditions which cannot be exactly 

 imitated on the earth's surface. For meteorological pur- 

 poses the usefulness of a free balloon is, however, to a 

 certain extent limited by the fact that the balloon is an 



aerial navigation. During the exhibition fourteen com- 

 petitions were held, in which a hundred and fifty-six 

 ascents were made. The competitions were of four kinds; 

 for altitude, for duration of voyage, for distance and for 

 descent at a specified spot. The competitors were ex- 

 clusively French ; the greatest height reached was 8417 

 metres, the longest voyage in time lasted 3545 hours and 

 covered also the longest distance, namely, 1925 kilo- 

 metres ; the nearest approach to a given point was 

 within 400 metres, after a voyage of 32 kilometres. Of 

 the 156 voyages, 137 were completed within France, ten 

 extended to Germany, three to Belgium and three to 

 Holland, while three were not terminated until the Russian 

 frontier was passed. It is satisfactory to note that all 

 were conducted without accident either to aeronaut or 

 spectator. Among the many interesting photographs 

 obtained during these expeditions is one of the neigh- 

 bourhood of the Pantheon, Paris, taken from a height of 

 500 metres and reproduced fFig. 1) from an article by 



I.— Neighbourhood of ihc I'.imhi 



,,l.hccl f„ 



aerostat ; it is carried with the stratum of air supporting 

 it and the only motion relative to the atmosphere is a 

 vertical one. Wind as understood at the surface is 

 therefore beyond the scope of observation of the bal- 

 loonist, and all meteorological observations that are 

 dependent upon the motion of air are not primarily 

 suitable for the car of a balloon, where the air is calm 

 and still even in a rapidly moving atmosphere. 



The traveller can in clear weather estimate the rate at 

 which he is borne along by noting the places over which 

 he passes, and he can obtain permanent records of his 

 voyages by photographs taken from his car, which suggest 

 a curious reminiscence of old-fashioned maps. A photo- 

 graph ic camera is indeed the first and most natural item 

 in the equipment of a balloonist, whether the aim of his 

 voyage be scientific inquiry or merely adventure. One 

 of the most novel and successful departments of the Paris 

 exhibition of 1900 was the aeronautical section, which 

 gave full opportunity for the display of the powers of 



NO. 1680, VOL. 65] 



Commandant Renard in the Bulletin of the Societd 

 d'Encouragement pour I'Industrie Nationalc. For the 

 purpose of comparison, a photograph of Berlin from a 

 height of 2000 metres, taken m 1893 on one of the voyages 

 of the ill-fated balloon Humboldt, is also reproduced 

 (Fig. 2). It shows the Belle .Alliance Platz in the centre, but 

 the scale is evidently very small. A slightly larger view 

 (Fig. 3) of the central portion, taken on another occasion, 

 is here reproduced from the frontispiece of Prof. 

 Assmann's memoir, " Die Modernen Methoden zur 

 Erforschung der Atmosphare mittels des Luft-ballons 

 und Drachen," which appeared in the March and April 

 numbers of Hinimel umt Enle last year. 



.\mong the best known establishments for exploring 

 the upper air are those of M. Teisserenc de Bort at 

 Trappes for " ballon sondes " and kites and Mr. Lawrence 

 Rotch for kites at Blue Hill, Massachusetts ; but the general 

 use of balloons for scientific purposes has been carried out 

 most effectively at Berlin. By means of funds supplied 



